Answer:
10.64
Explanation:
Let's consider the basic reaction of cyclohexamine, C₆H₁₁NH₂.
C₆H₁₁NH₂(aq) + H₂O(l) ⇄ C₆H₁₁NH₃⁺(aq) + OH⁻ pKb = 3.36
C₆H₁₁NH₃⁺ is its conjugate acid, since it donates H⁺ to form C₆H₁₁NH₂. C₆H₁₁NH₃⁺ acid reaction is as follows:
C₆H₁₁NH₃⁺(aq) + H₂O(l) ⇄ C₆H₁₁NH₂(aq) + H₃O⁺(aq) pKa
We can find the pKa of C₆H₁₁NH₃⁺ using the following expression.
pKa + pKb = 14.00
pKa = 14.00 - pKb = 14.00 - 3.36 = 10.64
PH of acidic buffer = pKa + log [CH₃COONa - HCl] / [CH₃COOH + HCl]
pKa of CH₃COOH = 4.74
Concentration of acetic acid in buffer = 2.0 M
Concentration of sodium acetate = 1.0 M
Concentration of HCl must add = x
pH = 4.74 + log (1-x) / (2+x) = 4.11
x = concentration of HCl must be added = 0.43 M
number of moles of HCl = M * V = 0.43 * 1 = 0.43 mol
mass of HCl must be added = 0.43 * 36.5 = 15.7 g
The chemical reaction involving sodium and oxygen as given in the reaction: 4Na + O2 → 2Na2O is a synthesis reaction.
<h3>What are chemical reactions?</h3>
Chemical reactions are changes which occur in the chemical composition of atoms of substances which results in the formation of new substances.
There are different types of chemical reactions such as:
- synthesis reaction
- displacement reaction
- double displacement reactions
A synthesis reaction is a reaction in which two or more substances combine to form a new product.
Therefore, the chemical reaction involving sodium and oxygen as given in the reaction: 4Na + O2 → 2Na2O is a synthesis reaction.
Learn more about chemical reactions at: brainly.com/question/11231920
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Explanation:
What is true about an atom in an excited state? Select all that apply:
A. It is less likely to enter chemical reactions.
B. It is more likely to enter chemical reactions.
C. It has less energy than a ground state atom.
D. It has more energy than a ground state atom.
<u>Answer:</u>
a) number of neutrons
<u>Explanation:</u>
A sodium ion is formed when an electron is removed from a sodium atom. This means that the atom's number of electrons changes, but the number of neutrons remains unchanged.
However, as the number of electrons changes, the electric charge and the electronic structure change, which means that a sodium atom and a sodium ion do not have the same number of electrons, nor do they have the same electric charge or electronic structure.
Therefore, option a) is the correct option.
